1. Field of the Invention
The present invention relates primarily to a method and apparatus for applying an identifying marking on articles such as polypropylene battery cases, and in particular to a method for applying a rubber patch to such devices.
2. Description of the Prior Art
It is often desirable to provide markings for batteries or battery cases to discourage unauthorized replacement or transfer thereof, particularly in respect to commercial operation of vehicles. Automobile rental agencies, for example, have particular need for permanently providing each battery on their automobiles which are leased with identification marking. This is true in particular because of the possibility of unauthorized interchange or substitution while the automobiles are beyond the agency's control for an extended period. In addition, public service commissions in many states require that trucking companies apply a variety of identifying indicia to trucks and trailers operating across particular states. These requirements make additionally desirable an inexpensive, convenient means of applying such markings.
Batteries may be provided with a serial number, usually having many digits, and typically of quite small dimension. These numbers are difficult to read, and may be positioned in a manner that makes the numbers inaccessible for viewing. The present invention provides a method and apparatus for applying identifying markings to articles such as batteries, and which provides an attractive and easily read marking. In U.S. Pat. No. 2,985,216, issued on May 23, 1961 to Williams, there is disclosed a method and apparatus for applying markings to vehicle tires. In accordance with that patent, a tire applique was provided which comprised a pad of rubber laminations of contrasting color. Identifying perforations were die cut into the pad laminations to provide the markings. An improved method and apparatus for marking tires is disclosed in U.S. Pat. No. 4,256,159, also issued to Williams on Mar. 17, 1981.
In U.S. Pat. No. 1,544,262, issued to Midgley on June 30, 1925, there is disclosed a method for marking rubber. Under the Medgley procedure, tires are formed with stocks of contrasting shades. Heat is applied to the tire to react upon the rubber mixture to produce a change of shade at this location. Coating devices formed with tires are disclosed in U.S. Pat. Nos. 3,225,810, issued to Enabnit on Dec. 28, 1965, and 3,233,647, issued to Newell on Feb. 8, 1966.
A variety of other marking materials or methods are shown in the prior art. A pneumatic rubber tire with adherent polyurethane sidewall is disclosed in U.S. Pat. No. 4,182,393, issued to Larson et al. on Jan. 8, 1980. A tire sidewall facing is also described in U.S. Pat. No. 3,449,201, issued to Palmquist et al. on June 10, 1969. A method and means for applying legends or designs to tires is described in U.S. Pat. No. 1,371,501, issued to McLane on Mar. 15, 1921. Decorative plaques and transfers are described in U.S. Pat. Nos. 4,125,655, issued to Kanzelberger on Nov. 14, 1978, and 2,625,496, issued to Swift et al. on Jan. 13, 1953.